I am doing an engine swap on my yj. I have a 1978 chevy 350, I do not know what it is out of. My transmission is out of a 1989 chevy 2500. I bought a 168 tooth flywheel for a 1978 truck. Does anyone know if I need an 11 or 12 inch clutch. When I go to the parts store they have 11 and 12 inch diaphram and lever style clutches for a 1978 truck. I have know idea which one to get or even if it matters.